It was a sensational political scandal most under 40 likely never heard of. In July, 1969 – as Apollo 11 was on its way to the moon - Sen. Ted Kennedy left a party on the Massachusetts island of Chappaquiddick and drove off a bridge.

He survived. Mary Jo Kopechne, a passenger and campaign worker for his late brother Bobby, drowned in the car.

Jason Clarke prepares to spin-doctor the nation as Ted Kennedy in Chappaquiddick

And it’s noteworthy that, in John Curran’s movie Chappaquiddick, these two key players in a great American tragedy are portrayed by actors best known as comedians. Gargan – who emerges as the conscience of the movie – is played by The Hangover’s Ed Helms. Markham, one of Kennedy’s prime enablers, is standup comic Jim Gaffigan.

“That particular scene is very serious, very straightforward,” Gaffigan told me while promoting a standup performance in Toronto. “The movie has humourous moments, unintentionally, but few of them fall on us, and Ed’s role is especially dramatic.”

Like many comedians, Gaffigan has a desire to be taken seriously, one he’s literally acted upon. In 2011, he co-starred on Broadway with Kiefer Sutherland in a production of Jason Miller’s Pulitzer-winning That Championship Season. And his role in Chappaquiddick came on the heels of his best-friend role opposite Liev Schreiber in the Chuck Wepner boxing biopic The Bleeder (which debuted at the Toronto International Film Festival in 2016 and has since been retitled Chuck).

It’s a big bite of dramatics in a short time, one that involved training in a Bayonne, New Jersey accent for The Bleeder, and a quick shift in gears to a Massachusetts one for Chappaquiddick. “Some comedians think of acting strictly as a career move,” he says. “I really do enjoy it. You get to dress up like you’re from the ‘60s (in Chappaquiddick) or the ‘70s (in The Bleeder) and pretend.

“I don’t take my breaks for granted. A lot of my comedian friends are actually great actors and haven’t had the opportunities.”

Gaffigan as Massachusetts State Attorney Paul Markham in Chappaquiddick

Chappaquiddick was an eye-opening experience socially for Gaffigan, focusing as it did on power, protection, spin, and the whole calculated public relations effort to turn Kennedy (Jason Clarke) from the perpetrator of a criminal offense to a victim. (Drawing attention away from the actual victim, Kopechne, played by Kate Mara).

“I think if Chappaquiddick happened today, Ted Kennedy would be in jail, beyond a doubt,” Gaffigan says. “Culturally we’re dealing with the question of white entitlement and Senatorial and Kennedy entitlement.

“It’s really fascinating, the vibe that was there. It’s weird enough these days to see people in a movie chain-smoking. But at Chappaquiddick, the party was kind of a reunion for people that had worked on Bobby’s campaign. And there were so many layers of darkness. A lot of alcohol. Six married men, six single women.

“Some people think this movie is a hit-piece. But if anything, it’s a very human story. Ted Kennedy was in the position he was in, the last of his brothers left alive. The entire nation was kind of looking at him to step up and be president. There were a lot of layers of tragedy to what happened that night.”

CHAPPAQUIDDICK – REVIEW BY JIM SLOTEK

Rating: B

Between the time the movie Chappaquiddick was shot and its release this week, the #MeToo movement happened, making its events even more resonant and deplorable in retrospect.

To recap: As a groundswell of demand built for a reluctant Ted Kennedy (Jason Clarke) to carry the Camelot torch and run for president, Ted and his cronies held a party on Chappaquiddick island on the premise of it being a reunion of the Boiler Room Girls, the women staffers who’d worked for the late Bobby Kennedy. Among them was an ambitious young campaign worker named Mary Jo Kopechne (an under-used Kate Mara).

As the party hits full swing (hinting at, but not explicitly showing the sexual side of the event), the boozy speculation turns to whether the “Girls “will indeed revisit the campaign trail. Ted makes a toast, declaring them all to be “family,” and de facto Kennedys.

John Curran’s movie is really about the bubble the feckless youngest Kennedy brother lived in, and the extent to which others were willing to mobilize as his enablers.

In fact, Curran practically hits you over the head with that fact at times. After Ted and Mary Jo’s drunken drive off the bridge, the unethical intervention by Ted’s cousin Joe Gargan (Ed Helms) and Massachusetts State Attorney Paul Markham (Jim Gaffigan), and Kennedy’s ill-advised return home before contacting the police, the hungover Boiler Room Girls are told that one of their best friends is dead.

After a few surprised sobs, one asks, “How can we help the Senator?”

Mary Jo practically turns invisible from the moment of her death. Even old Joe Kennedy (Bruce Dern), enfeebled and paralyzed from a stroke manages to croak one word over the phone to his son – not once but twice – “Alibi.”

Chappaquiddick really hits its stride when the Kennedy damage machine goes into full swing, with the terrific character actor Clancy Brown taking over as former Secretary of Defense and family fixer Robert McNamara – telling doctors what their diagnosis is going to be, pulling favours to expedite the court date (the better to rush a slap-on-the-wrist ruling).

Unfortunately, this is also where Ted Kennedy practically backs away from his own movie. As others take control, the narrative only leaves him with a decision over whether or not to do the right thing. And we all know what that decision eventually was. The man would become one of the Senate’s great lawmakers, but it was built on a lie.

The one who really runs away with the movie’s defining moment is Helms (who has shown terrific ability in movies like Cedar Rapids). Where Clarke’s Ted is a blank slate whose state of mind is only ever revealed by his actions, Helms’ Gargan practically becomes a man of principle in front of our eyes.

(Worth staying for: A during-the-credits roll of actual people being interviewed in the wake of Chappaquiddick saying they’d still vote for Ted Kennedy no matter what he did. Eerie in the age of Trump).